Restless legs syndrome (RLS) is a disorder that causes unpleasant sensations in the legs and an urge to move them. Symptoms are usually worse at night and can interfere with sleep. RLS affects more women than men and risk increases with age. While the cause is unknown, genetics and medical conditions like iron deficiency are thought to play a role. Diagnosis is based on symptoms as there are no medical tests. Treatment focuses on lifestyle changes and medications to improve sleep and quality of life.